Homeostatic Control of Deep Sleep and Molecular Correlates of Sleep Pressure in Drosophila
Abstract
Homeostatic control of sleep is typically addressed through mechanical stimulation-induced forced wakefulness and the measurement of subsequent increases in sleep. A major confound attends this approach: biological responses to deprivation may reflect a direct response to the mechanical insult rather than to the loss of sleep. Similar confounds accompany all forms of sleep deprivation and represent a major challenge to the field. Here we describe a new paradigm for sleep deprivation in Drosophila that fully accounts for sleep-independent effects. Our results reveal that deep sleep states are the primary target of homeostatic control and establish the presence of multi-cycle sleep rebound following deprivation. Furthermore, we establish that specific deprivation of deep sleep state results in state-specific homeostatic rebound. Finally, by accounting for the molecular effects of mechanical stimulation during deprivation experiments, we show that serotonin levels track sleep pressure in the fly's central brain. Our results illustrate the critical need to control for sleep-independent effects of deprivation when examining the molecular correlates of sleep pressure and call for a critical reassessment of work that has not accounted for such non-specific effects.
Data availability
All Raw Data is available at Dryad.
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Homeostatic Control of Deep Sleep and Molecular Correlates of Sleep Pressure in DrosophilaDryad Digital Repository, doi:10.5061/dryad.qnk98sfpp.
Article and author information
Author details
Funding
National Institute of Neurological Disorders and Stroke (R21NS131939)
- Orie T Shafer
National Institute of Neurological Disorders and Stroke (R01NS077933)
- Orie T Shafer
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2023, Chowdhury et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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